Starter ignition switch



May 25, 1954 w. w. MILLER STARTER mnmou swI'rcH 2 Sheets-Sheet 1 FiledJuly 16 1951 y 5 w. w. MILLER 2,679,557

sm'rsa murrxou swrrcu Filed July 16, 1951 2 Sheets-Sheet 2 Patented May25, 1954 UNITED STATES PATENT OFFICE STARTER IGNITION SWITCH of DelawareApplication July 16, 1951, Serial No. 236,944

1 Claim.

The present invention relates to new and useful improvements inautomobile ignition switches, and more particularly to new and usefulimprovements in rotary contact mechanism for ig nition switches andmeans to impart rotation to and position the contact mechanism.

The principal object of the present invention is to provide an ignitionswitch of novel construction which, in addition to the usual oil." on"and "accessory" positions, has a position wherein a circuit is completedto the starting motor.

Another object of the present invention is to provide a novel ignitionswitch of the stated type wherein a single contact plate formed from asheet of conducting material may be used to complete all of the requiredcircuits through the switch.

Another and equally important object of the present invention is toprovide an ignition switch as set forth having a novel construction andarrangement of cam and follower to limit different positions of theswitch mechanism.

These and other objects of the present invention and the variousfeatures and details of the operation and construction thereof arehereinafter more fully set forth and described with reference to theaccompanying drawings, in which:

Fig. 1 is a side elevational view of an ignition switch made inaccordance with the present invention;

Fig. 2 is an end elevational view of the switch illustrated in Fig. 1;

Fig. 3 is an enlarged longitudinal sectional view illustrating theconstruction of the switch;

Fig. 4 is a transverse sectional view taken on line 4-4, Fig. 3;

Fig. 5 is a transverse sectional view taken on line 5-5, Fig. 3;

Fig. 6 is a transverse sectional view taken on line 3--6, Fig- 3;

Fig. '7 is a fragmentary sectional view taken on line |--'l, Fig. 5;

Figs. 8 to 11, inclusive, are schematic sectional views illustrating theposition of the contact plate with respect to the contact terminals inthe various operating positions of the switch;

Fig. 12 is a developed contour of the lock detent path starting fromline A in Fig. 4, counterclockwise;

Fig. 13 is a perspective view of the contact rotor;

Fig. 14 is a perspective view of the rotor adaptor;

Fig. 15 is a perspective view of the rotor base which carries thecontact plate; and,

Fig. 16 is a perspective view of the contact plate.

Referring more specifically to the drawings and particularly Figs. 1 and2 thereof, reference numeral 20 designates generally an ignition switchwhich comprises a switch housing 2| having at the front end thereof theusual lock cylinder 22 and at the other end thereof a plurality ofterminals 23, 24 and 25 arranged about a central terminal 25.

In accordance with the present invention the terminals 23, 24, 25 and 26extend through an insulating switch base 21 and provide terminalcontacts 23a, 24a, 25a and 25a interiorly of the housing 21. Thesecontacts are arranged for engagement selectively by a metal contactplate 28 which is carried by a rotatably mounted switch plate member 29.

As illustrated in Fig. 16, the contact plate 28 comprises an annularring having a central opening 32 therein. Cut out portions 33 and 34along the outer periphery of the ring and a third cut out portion 35along the periphery of the central opening 32 allow the contact plate 23to complete the desired circuits through the terminal contacts. Aplurality of forwardly extending lug portions 36 on the contact plate 28are utilized to secure the latter to the switch plate member 29 in therelation shown in Fig. 13.

The switch plate member 29 is rotatably mounted on a lug 31 formed as anintegral part of the central terminal 26. Rotation is imparted to theswitch plate member 29 by means of bridge piece 38 constructed asillustrated in Figs. 13 and 14. The bridge 38 comprises a forwardcylindrical head portion 39 and rearwardly extending parallel legportions 42. Extending laterally outward from the free ends of the legs42 are lugs or fingers 43 which are constructed to be received in slots44 formed in the rotary switch plate 29 and provide a rotational drivingconnection between the bridge 38 and the switch plate 29.

Rotation of the entire rotor assembly including the contact plate 23,the switch plate member 29 and the bridge 38, arranged as shown in Fig.13, is effected by turning a key in the lock cylinder 22. Extendingoutwardly from the rear surface of the lock cylinder 22 is a generallyrectangular tang portion 45 which is received in a similarly shaped slot46 in the head portion of the bridge 38. Rotation of the ignition key inthe lock cylinder 22 causes similar rotation of the tang 45 therebyimparting rotation to the switch assembly.

Figs. 8 to 11 inclusive of the drawings illustrate the position of thecontact plate 28 with respect to the contact terminals for the variouspositions of the ignition switch. The contact plate 28 is insulated fromthe switch housing and may be energized through the contact terminal 23awhich in most instances is connected to the ammeter on the dashboard ofan automobile. In the "off position of the switch shown in Fig. 8, theconnection between the contact plate 28 and the terminal 23a is brokenso that there is no current passing through the switch.

In order to start the motor the contact plate 28 is rotated in theclockwise direction to the position illustrated in Fig. 9 in which itcontacts the terminals 23a, 24a and 26a. Contacting the terminal 24acompletes the ignition circuit to the motor and the circuit to thestarting solenoid of the starting motor is completed through the contactterminal 26a. After the motor has started the contact plate is rotatedin the counterclockwise direction to the position illustrated in Fig. 10thus bringing the contact terminal 26a into alignment with the cut outportion 35 of the contact plate and breaking the circuit to the startingsolenoid but still maintaining an unbroken ignition circuit. In thisposition of the switch, the accessory circuit is completed through thecontact terminal 23a which is engaged by the contact plate 28.

In order to complete solely the circuit to the car accessories thecontact plate 28 is rotated in a counter-clockwise direction to theposition illustrated in Fig. 11 contacting the terminals 23a and 25awhich completes the circuit through the ignition switch to theaccessories.

In accordance with the present invention means are provided to properlyposition the contact plate 28 with respect to the terminals for thevarious settings of the ignition switch. To this end, there is providedon the forward inner surface of the switch housing 2| diametricallydisposed semi-circular cam tracks 41, 41 which are arrangedconcentrically of the rotational axis of the switch rotor assembly. Apin 48 having its opposite ends disposed in cooperative engagement withthe cam tracks 41, 41 is slidably mounted in slots or guideways 49extending lengthwise of the leg portions 42 of the bridge member 38. Acoil spring 52 is positioned within the bridge piece 38 and between thepin 48 and the switch plate 29 and this spring operates to maintain thepin 48 yieldingly in engagement with the cam tracks 41, 41 while theslots or guideways 49 permit the pin 48 to be displaced against thespring 52 in accordance with variations in the height of the cams.Rollers 5|, 5| at the ends of the pin 40 enable the pin to roll easilyon the surface of the cam tracks 41, 41.

A smaller coil spring 53 is positioned at the outer side of the pin 48between it and the forward wall of the bridge piece 35. By thisconstruction the pin 48 is held under the opposing pressures of thesprings 52 and 53 so that rattling of the pin is precluded and thespring 53 in conjunction with the spring 52 maintains the bridge 38against the lock cylinder 22, thereby preventing rattling of the lockcylinder 22.

A developed contour of the cam surface is illustrated in Fig. 12 of thedrawing in order to show the relative positions of the pin 48 withrespect to the cam track 41 in the various settings of the ignitionswitch. Each cam track 41 has three low portions 54, 55 and 56 in whichthe pin 48 may be engaged when the switch is turned to its "oflposition, on position, or "accessory position, respectivelyfas shown inFigs. 8, l0 and 11. These low portions of the cam track serve toproperly position the contact plate with respect to the contactterminals.

When the contact plate 28 is rotated to its extreme clockwise position,as illustrated in Fig. 9, in order to complete the circuit to thestarting solenoid the pin 48 rides up the cam track 41 to the right-handstops 51, 51 as shown in Fig. 12, and upon release of the ignition keythe pin 48 and cam track 41 in cooperation with spring 52 cause theswitch rotor to move counterclockwise to the on position in which thepin 48 is positioned at the low portion 55 of the cam track 41. Theextreme counterclockwise position of the contact rotor is limited by theleft-hand stops 5B which are adjacent to the low portions 56 on the camtrack 41.

From the foregoing it will be observed that the present inventionprovides a novel ignition switch which, in addition to the usual ofi,"on and accessory positions also has a position wherein a circuit iscompleted to the starting motor. The invention also provides an ignitionswitch having a novel construction of cam and follower to limit thedilierent positions of the switch mechanism. Furthermore, the presentinvention provides a novel ignition switch wherein a single contactplate formed from a sheet of conductin material may be used to completeall of the required circuits through the switch. In addition, thepresent invention provides a novel ignition switch having the featuresand characteristics set forth which is easily and cheaply manufacturedand is entirely eflicient and eiiective in operation and use.

While a particular embodiment of the present invention has beenillustrated and described herein, it is not intended to limit theinvention to such disclosures, and changes and modifications may be madetherein and thereto within the scope of the following claim.

I claim:

In a starter ignition switch comprising a generally cylindrical housinghaving a plurality of contact terminals positioned interiorly thereof, aswitch plate assembly in said housing mounted for rotary movement aboutthe longitudinal axis of said housing, a contact plate carried by saidswitch plate for engagement with said contact terminals, a bridge piececomprising a cylindrical head portion and forwardly extending parallelleg portions terminating in lugs engaging said switch plate and actuableto impart rotation thereto, a cam track arranged concentrically aboutthe rotational axis of said switch plate adjacent the junction betweenthe head and leg portions of said bridge piece, a detent pin mounted inlongitudinal slots in the parallel leg portions of said bridge piece,spring means intermediate said leg portions in engagement with saidswitch plate resiliently urging said detent pin into engagement withsaid cam track, and second spring means positioned between said detentpin and the cylindrical head of said bridge piece to prevent rattling ofsaid bridge piece, said second spring means being weaker than said firstspring means whereby said first spring means maintain the detent pin inengagement with the cam track.

Name Date Jacobi May 4, 1948 Number

